Spiribacter aquaticus Leon et al. 2017 is a later heterotypic synonym of Spiribacter roseus Leon et al. 2016. Reclassification of Hatopeptonelta vilamensis Menes et al. 2016 as Spiribacter vitamensis comb. nov.

A comparative taxonomic study of Spiribacter and Halopeptonella species was carried out using a phylogenomic approach based on comparison of the core genome, orthologous average nucleotide identity (OrthoANlu), Genome-to-Genome Distance Calculator (GGDC) and average amino acid identity (AAI). Phylogenomic analysis based on 976 core translated gene sequences obtained from their genomes showed that Spiribacter aquaticus SP30(T). S. curvatus UAH-SP71(T). S. roseus SSL50(T), S. salinus M19-40(T) and Halopeptonella vilamensis DSM 21056(T) formed a robust cluster, clearly separated from the remaining species of closely related taxa. AM between H. vitamensis DSM 21056(T) and the species of the genus Spiribacter was >= 73.1%, confirming that all these species belong to the same single genus. On the other hand, S. roseus SSL50(T) and S. aquaticus SP30(T) showed percentages of OrthoANlu and digital DNA-DNA hybridization of 98.4% and 85.3 %, respectively, while these values among those strains and the type strains of the other species of Spiribacter and H. vilamensis DSM 21056(T) were <= 80.8 and 67.8%, respectively. Overall, these data show that S. roseus SSL50(T) and S. aquaticus SP30(T) constitute a single species and thus that S. aquaticus SP30(T) should be considered as a later, heterotypic synonym of S. roseus SSL50(T) based on the rules for priority of names. We propose an emended description of S. roseus, including the features of S. aquaticus. We also propose the reclassification of H. vilamensis as Spiribacter vilamensis comb. nov.